At present multiple devices intended for the transportation and use of water for extinguishing fires are known, which devices store a considerable amount of water and are transported by vehicles, both by land and air, to the fire area, usually an area exposed to the outside and of a certain extension, such as a forest fire, industrial facilities or a building of considerable size.
The use of a helicopter as a means of transport is a great advantage, as the helicopter moves fast between the water loading point and the discharge point into the fire, it can carry a significant amount of water, and it discharges accurately and can also load in tight spaces where seaplanes cannot land.
Some of the anti-fire and helicopter transported devices include a semi-rigid open top reservoir provided with slings or cables for its suspended fixation from a helicopter and a lower discharge hatch, which can be operated by the pilot. The loading of this reservoir can be made at any pond and pool but the loading speed depends on the pilot's skill to achieve immersion of the reservoir since the loading is performed through the top opening. Other disadvantages of these devices are: they require that the height of water in the loading area is higher than that of the reservoir as the loading is performed through its top, and that during transport part of the load may be lost as the reservoir is permanently opened at its top.
Other known devices include a rigid belly-tank, permanently installed on the bottom of the helicopter and equipped with a hydraulic pump and a hose for loading said tank, while the unloading is done through hatches or trapdoors at the bottom of the tank. The helicopter equipped with this device is more stable in flight and can reload in shallow areas. However, loading the water with the hydraulic pump is slow and the whole device is very heavy with respect to the water that it can carry.
In the patent RU 2197308 C2 an extinguishing fire apparatus from a helicopter is described comprising a loading tank connected to a vacuum pump which carried out a suction of air inside the tank during the water loading operation in order to facilitate the filling thereof.
The patent application WO 2008/071825A2 describes a helibucket for fire-fighting helicopters that has a flexible container provided with a filling pump equipped with level sensors for its automatic operation and stop when the helibucket touches the water, the unfolding of the helibucket and opening and closing of the loading hatches being performed by means of a system of cables.
This helibucket has maximum and minimum level sensors to control and amount of water that is loaded.